Auto-tuning method based on fuzzy reasoning for speed controller in vector-controlled induction motor drives

The authors present a novel autotuning method based on fuzzy reasoning for the speed controller (proportional-integral or PI controller) in vector-controlled induction motor drives. The trajectory of the step response of motor speed described in the phase plane is used to examine the gain parameters of the PI controller. To obtain appropriate gain parameters, fuzzy inference is implemented offline at two characteristic points defined on this phase trajectory. Fuzzy control rules are devised on the basis of the principle that the gain parameters have appropriate values if these characteristic points exist at the origin in the phase plane. This method is applied to a model drive system with a 0.75 kW induction motor. Simulation results show that the validity of this autotuning method